I have a 2007 Mazda3 GT Sport Hatchback that the FOB no longer locks the doors, nor does it start the car horn and flash the lights if pressed a second time. I had a second FOB (Valet) that also does not lock the doors. I replaced both batteries and verified the circuit boards for the Fobs were ok and still no success. I tried re-programming both Fobs and the results were positive (according to the program guides) however afterwards they still do not lock the doors. In addition, locking all 5 doors works fine when using the key manually outside the door or by pushing the lock / unlock button inside the door. I have checked several Mazda sites and still have no answer. I am thinking it's the Keyless Remote Control Module behind the glove compartment but before purchasing one would like confirmation that the module is bad. I have no idea how to test it. Any help with this would be appreciated, thanks.

 

Is you key separate to the remote or do you have the flip key?

 

Separate, the older version

 

It's not uncommon for the remotes to go bad with age.

Before you replace the keyless entry module ( which will require programming to your car &/or remotes)

I suggest visiting either a Mazda dealership or a locksmith to get the remotes checked/tested/reprogramed.

 

Good point and thanks. Since the FOB is separate to the key, I believe I can buy either a used or new FOB off of Ebay etc.

 

Yes, & get it programmed to your car.

 

One thing I forgot to mention and should have... my apologies. When I first noticed the problem the "door ajar" light on the console went on and stayed on. No matter how many times I opened and closed all 5 doors. I pulled the 15A Room Fuse as the console lights and door ajar indicator were on all the time and using up the battery. When driving the car interestingly enough the door ajar light comes back on and stays on so it must be on a split circuit.

 

You will need to fix the "Door Ajar" issue before you worry about remotes.

 

Yes I agree and why my initial thinking was that the fault was with the Keyless Command Module. All 5 doors lock perfectly from the inside and outside using the key manually. So the fault could also be one of the Actuator's sending a false signal saying door is ajar. I disconnected the Actuator at the hatchback trunk lid but door ajar was still lit so I am at a loss?

 

If the module detects a "door Ajar" signal it will disable the keyless entry, basically it thinks a door is still open. The door lock button & key barrel are purely a mechanical system.